Our recent frost killed these vines, and so I dug around in the ground for any developing sweet potatoes. I discovered a good many, mostly small (as in this photo) with the exception of a half dozen large (a few covered with scavenging bite marks - moles perhaps?).
We have now had several meals with "sweet potato fingerlings." Scrub the potatoes then toss them with olive oil and kosher salt. Bake in the oven until the outsides are crispy. Sort of like french fries.